| 摘要 |
PURPOSE:To measure the iron loss of a telephone-tunnel by providing search coils in juxtaposed main and auxiliary current conducting circuits, and disposing a simulated sample of the telephone-tunnel near the search coils in the state of making induced voltage zero. CONSTITUTION:Current I is supplied, via a transformer 5, to juxtaposed conductors 1c, 1d forming respectively main and auxiliary current conducting circuits 1a, 1b. A variable resistor 7a and variable resistor 7b connected to a mutual rectance 6 are adjusted while a power meter 8 is in observation so that the voltage induced by search coils 3a, 3b for detecting the magnetic flux formed by a voltage lead wire 2 wound on the conductors 1c, 1d is made zero. Then the resistance components and reactance components of the circuits 1a, 1b, the voltage dividing ratio of the resistors 7a, 7b, the inductance of the reactance 6, etc. satisfy required conditions and if a simulated sample 4 of a telephone-tunnel is disposed near the coil 3a, the input voltage to the power meter 8 is the voltage value corresponding to the loss by the sample 4 alone and the iron loss of the telephone-tunnel is measured with high accuracy. |
